The present invention relates to the field of finishing of documents and other printed or sheet materials. More particularly, the present invention relates to an improved and more efficient device and method for creating multiple punch holes during the finishing process of paper sheets and other materials. A highlight of the present invention is the ability to select between at least two configurations of punch holes automatically, without manual adjustment, and “on-the-fly” without interruption of the sheet or paper flow.
A common finishing process for documents and other printed matter is the punching of holes to allow sheets to be bound in a standard ring binder. Such binders are inherently flexible since they allow rearrangement of the order of sheets and allow insertions and deletions at will. Probably most students in the western world are familiar with the multi-ring school binder for homework, assignment papers, teacher handouts, etc. Multi-ring binders are also standard in many reference anthologies for the flexibility described above. As an example, volumes published by publisher Commerce Clearing House relating to various legal subjects such as tax, labor law, etc are found in virtually all legal libraries within the United States and are published in a standard 4-ring binder arrangement.
Reams of paper can be purchased with holes pre-punched during the paper production process. Most paper and sheets to be printed, however, are purchased without the pre-punching of holes. Such unpunched sheets allow users the flexibility of deciding if holes are to be subsequently punched, and, if punched, which configurations to use. There are many standard and non-standard punch configurations currently in use. The 3-hole punch arrangement of 8.5×11 inch (B4) paper is a North American standard although, as discussed above, 4-hole punch arrangements are also standard for some purposes. In Europe, A4 paper is typically punched in a 4-punch arrangement. Of course, paper that differs in size from A4 or B4 typically require different arrangements and spacings of punches.
Currently, for production processes requiring punch holes in sheet materials, production choices are limited. As described above, paper can often be purchased with holes-pre-punched. Yet such purchase requires advance knowledge of requirements and increased inventory costs. Finishing equipment can also be purchased that is capable of making hole punches at document production rates. Such punch hole finishing equipment has several limitations, however. First, hole punch apparatus in the prior art either requires a fixed arrangement of punches or requires that the production run be stopped in order to manually change the punch arrangement. Such work stoppage Is non-economic when the finishing processes are arranged in-line with expensive production equipment such as large lithographic presses or high speed reprographic systems such as modern electrophotographic production printers. A second limitation to current hole punch apparatus is that in order to provide for multiple hole punch arrangements without stopping the work flow, multiple punch stations must be inserted in the work flow line. Such multiple punch stations require additional capital investments and, more importantly, take valuable space.
It would be advantageous to have an apparatus that takes little or no space in an in-line finishing process that enables at least two and possibly more punch hole arrangements. With such a small footprint device, such flexible punch apparatus could be contained within the typical cabinets of high speed production electrophotographic printers and high speed finishing equipment in-line from high-speed lithographic and other presses. With such a device, a document production or other production line that typically uses two or three different punch arrangements can build the flexible punch of the present invention into standard production equipment and can avoid either the expense of duplicate equipment or the inventory cost and management problems resulting from acquiring pre-punched sheet materials. With the small foot-print size of the present invention, additional finishing capability can be built into printers and similar equipment without requiring production stoppage in order to change the punch arrangement.